Is UCP2 gene polymorphism associated with decreased resting energy expenditure in nondialyzed chronic kidney disease patients?
OBJECTIVE
The deletion/deletion (del/del) polymorphism of uncoupling protein 2 (UCP2) was associated with decreased energy expenditure in diabetic and obese patients. There is evidence of decreased resting energy expenditure (REE) in chronic kidney disease (CKD) patients not yet on dialysis. However, whether REE is associated with the UCP2 polymorphism was not previously investigated in this population. This study evaluated whether the del/del polymorphism of the UCP2 gene is associated with lower REE in nondialyzed CKD patients.


METHODS
This was a cross-sectional study.


METHODS
Forty-four nondialyzed CKD patients (29 male; aged 52 +/- 12 years; creatinine clearance, 37 +/- 13 mL/min/1.73 m(2) [values are mean +/- SD unless otherwise noted]) were included. Their REE was assessed by indirect calorimetry, and body composition by bioelectrical impedance. High-sensitivity C-reactive protein (hs-CRP) was also evaluated. The insertion/deletion (ins/del) polymorphism of the UCP2 gene was determined in all participants. To test whether the deletion/deletion (del/del) polymorphism of the UCP2 gene was associated with lower REE, the REE of carriers of the del/del genotype (n = 24; group Del) was compared with that of carriers of the insertion and ins/del genotype (n = 20; group Ins).


METHODS
The main outcome measure was REE.


RESULTS
The REE of group Del was similar to that of the group Ins (1379 +/- 239 kcal/day vs. 1360 +/- 289 kcal/day, respectively, P = NS). This result was maintained even after the REE was adjusted for lean body mass by analysis of covariance. In addition, in a multiple-regression analysis using REE as the dependent variable, only lean body mass and hs-CRP were significant predictors of REE.


CONCLUSIONS
The results suggest that the del/del polymorphism of the UCP2 gene is not associated with lower REE in nondialyzed CKD patients.
Avesani
Carla Maria
CM
Department of Medicine, Division of Nephrology, Federal University of São Paulo, São Paulo, Brazil.
Kamimura
Maria Ayako
MA
Utaka
Simone
S
Pecoits-Filho
Roberto
R
Nordfors
Louise
L
Stenvinkel
Peter
P
Lindholm
Bengt
B
Draibe
Sergio Antônio
SA
Cuppari
Lilian
L
D001481:Basal Metabolism / Q000235:genetics*; D001823:Body Composition / Q000502:physiology; D002097:C-Reactive Protein; D002153:Calorimetry, Indirect; D003404:Creatinine / Q000378:metabolism / Q000652:urine; D003430:Cross-Sectional Studies; D017097:Electric Impedance; D005260:Female; D017353:Gene Deletion; D005838:Genotype; D005919:Glomerular Filtration Rate / Q000502:physiology; D006801:Humans; D007473:Ion Channels / Q000235:genetics*; D007676:Kidney Failure, Chronic / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D024101:Mitochondrial Proteins / Q000235:genetics*; D011110:Polymorphism, Genetic; D000071246:Uncoupling Protein 2
D007473:Ion Channels; D024101:Mitochondrial Proteins; C000604389:UCP2 protein, human; D000071246:Uncoupling Protein 2; D002097:C-Reactive Protein; D003404:Creatinine